Chemotherapy-induced taste changes affect nutrition, quality of life

Although chemotherapy helps to prevent cancer growth in many patients, it also can destroy healthy cells that may cause taste changes and appetite loss. Many patients experience taste alteration as a common symptom but do not report it, and health care professionals may overlook the condition because it is not life-threatening.

A Turkish study reported that 67.7% of participants treated with chemotherapy experienced a change in taste. Researchers also found that 21.8% of patients were at moderate risk for malnutrition. Quality of life was also diminished in correlation with the intensity of taste changes.

Researchers found that patients with oral mucositis, dry mouth, gingival sensitivity, and gingival pain had a significantly higher severity of taste alteration and poorer quality of life. The study appears in Supportive Care in Cancer (doi:10.1007/s00520-025-09431-8).

The descriptive and cross-sectional study analyzed 330 patients, aged 18 years or older, who were receiving at least two outpatient chemotherapy treatments for cancer at a Turkish university hospital between March and June 2023. Participants were interviewed in person with the Descriptive Characteristics Form, the Chemotherapy-Induced Taste Alteration Scale, the Malnutrition Universal Screening Tool, and the World Health Organization Quality of Life Questionnaire.

More than half (57.6%) of the participants were 60 years old or older and female (51.8%). Thirty-seven percent of the participants were obese, 47.6% were smokers, and 27.6% had breast cancer; 39.7% were undergoing chemotherapy for five cycles or fewer, 40% were undergoing chemotherapy every 2 weeks, and 52% were not receiving any additional therapy.

Findings showed that 67.7% of the patients reported taste alterations of moderate severity, 77.9% had mouth sores, 88.5% had dry mouth, 83.9% had gingival sensitivity, and 17.9% had gingival pain. In the group, 21.8% were at moderate risk for malnutrition. More than half the patients (54.8%) lost weight after chemotherapy, and this correlated with significantly greater taste changes. Researchers identified a statistically significant correlation among taste alteration, malnutrition, and quality-of-life scores, with taste alteration being highly predictive of both conditions.

Taste alteration was higher in women than men and higher in patients with breast cancer than those with gastrointestinal, lung, urinary, or hematologic cancers. Taste alteration was lower in patients with a good or very good appetite in comparison with those with a poor or moderate appetite.

No statistically significant differences were found in taste alteration with age or the number of chemotherapy treatments between patients with a good or very good appetite and patients with a poor or moderate appetite.

Findings showed a statistically significant association between taste alteration and oral mucositis, dry mouth, gingival sensitivity and pain, rinsing the mouth with vinegar and carbonated water, and weight loss after chemotherapy. The use of mouthwash suggests that patients who suffered from taste changes tried a variety of ways to improve the symptom without success, the authors noted.

The authors recommended conducting randomized controlled trials, including the assessment of preventive or therapeutic care interventions, to help to reduce the incidence and severity of taste changes.

“The study addresses a really important question about how we think of some of the side effects of chemotherapy, and they’ve done a good and interesting job of characterizing the patient experience,” says Jennifer Douglas, MD, an assistant professor of otorhinolaryngology–head and neck surgery at the Hospital of the University of Pennsylvania in Philadelphia. “But the study did not include any objective measures such as formal taste tests that would quantify the degree and categorization of taste loss.”

Dr Douglas emphasizes the importance of objective measures for taste loss by noting that previous studies have shown differences between subjective and objective measures. She adds that another crucial component of food perception is smell, which researchers did not include in the study and should be further evaluated.

“We’re really only beginning to understand the tremendous impact that chemotherapy has on our senses of smell and taste and our experience of food and nutrition,” she says. “There’s a lot of literature that demonstrates when we rely on subjective measures only, we’re underestimating the degree of taste and smell loss.”

Dr Douglas says that future research should focus on quantifying the impact of different chemotherapies on taste and smell, identifying specific types of taste and smell impairments, and developing more targeted interventions to help patients to maintain nutrition and quality of life. One intervention may include creating foods that appeal more to patients by stimulating certain nerves in the mouth.

Joel B. Epstein, DMD, MSD, director of oral health services in the Division of Head and Neck Surgery at City of Hope in Duarte, California, notes that this study is unique because it correlates taste changes with nutritional outcomes.

“This study shows that taste alteration has an impact on patient-reported outcomes,” he says. “In the past couple of years, there’s been a huge increased interest in assessing the biology of taste change and potential management.”

In addition to being caused by chemotherapy, taste and smell changes can also occur with head and neck radiation therapy and immunotherapy, according to Dr Epstein.

Taste function is directly related to oral health and oral function. Saliva affects people’s ability to taste food. It does a better job than water in dissolving food molecules that interact with tastebud receptors and cause taste signaling, Dr Epstein points out. He adds that oncologists often overlook saliva function and should assess patients for it. At the same time, researchers must find ways to improve taste in patients with chemotherapy-induced taste alteration.

“The first step is to get taste molecules to the receptor site so the signaling can occur, suggesting we have the potential to do local and systemic therapies for taste,” he says. “As the biology of taste and smell is better understood we are looking to therapies that may regenerate tastebuds and affect taste.”

Some approaches include infrared-light therapy targeting nerve fibers, which may improve energy production and reduce inflammation, as well as methods to stimulate saliva and promote mucosal repair.

As the number of cancer survivors grows, oncologists are paying more attention to quality of life, taste, and nutrition, Dr Epstein says.

“There’s a gray zone between medicine, dentistry, and dieticians,” he says. “It really takes a team, and once we have the research, we’ll have better therapies.”

The team needs to collaboratively manage oral conditions, taste and smell function, and diet and nutrition to improve quality of life, Dr Epstein notes.